HALF-DAY
TUTORIAL T3:
Product design for manufacture is an
activity driven by descriptive information. Increasingly, design includes
the use of design constraints that impose conditions on the shape of the
product. That is, the designer states specific constraints without telling
the system in detail how to satisfy them. It is the task of the underlying
constraint solver to derive a plan by which to solve the constraint system.
This tutorial will be structured into two parts. In the first part, we describe
the architecture of a simple planar constraint solver anyone can implement.
We then discuss ways in which to extend the solver, both regards geometric
coverage as well as more complex constraints patterns. The second part addresses
spatial constraint solving focusing in particular on the algebraic side and
the techniques that are known for solving the equations.
Hoffmann's
research focuses on geometric and solid modeling and its applications in
science and engineering. He investigates geometric constraint systems, both
planar and spatial, and the application requirements on them in computer-aided
design. Hoffmann has a long-standing interest in robust semantics of geometric
computations. He also explores applications of geometric computation in
simulation and visualization. Recently, he has led the effort to simulate
and visualize the 9/11 attack on the Pentagon using finite element crash
analysis. Hoffmann is interim co-director of Purdue's Computing Research
Institute, dedicated to promoting interdisciplinary research involving computational
investigation. He is also co-director of the recently formed Center for
Product Lifecycle Management at Purdue.
Robert Joan-Arinyo is a Professor of Computer Science at the Universitat
Politecnica de Catalunya, Barcelona, Catalonia. He received a BS in chemical
engineering in 1971 and an MS in nuclear power plants engineering in 1976,
both from the Universitat Politecnica de Catalunya. After working for some
years in the industry he received a PhD in computer science from the Universitat
Politecnica de Catalunya in 1988. His research interests include solid modelling,
geometric constraint solving, high level languages for geometric representations
and graphic user interfaces for CAD. The author of numerous articles in these
fields, Professor Joan-Arinyo also works in the development of computer-based
simulation systems for endoscopic surgery.